A force limiter has the task of reducing load peaks in a safety belt system during the forward displacement of a vehicle occupant in the case of a vehicle impact. The use of such a force limiter is particularly effective in combination with a belt tensioner, which eliminates the belt slack, before the forward displacement of the vehicle occupant begins.
In the force limiters hitherto, the evolution of force over the path is only able to be predetermined within very rough limits, because despite small manufacturing tolerances with the same model it fluctuates from one force limiter to the other.
DE 42 06 117 C2 discloses a force limiter in a vehicle occupant restraint system, which comprises a tube, a piston element displaceably arranged in the tube and which is connected with a traction and thrust means and has a radial exterior having at least one ramp surface, and which further comprises at least one roller body which on displacement of the piston element in a direction of movement travels along the piston element up to a stop provided on the piston element, the at least one roller body being pressed radially outwards into a wall, plastically deforming the wall.